Li2SO4-K2SO4及NaCl-KCl对硼酸镁晶须结构与抗压强度的影响

Effect of Li2SO4-K2SO4 and NaCl-KCl on the Structure and Compressive Strength of Mg2B2O5 Whiskers

以硼酸和碱式碳酸镁为原料,采用原位合成法制备了硼酸镁晶须,研究了二元烧结助剂对硼酸镁晶须的结构及抗压强度的影响,并分别用TG、XRD和SEM对样品进行表征,分析得到硼酸镁晶须的过程转变机理及硼酸镁晶须的组成晶相和形貌。实验结果表明,当未添加烧结助剂时,孔隙率为62.57%,抗压强度为10.32 MPa,晶须直径为0.2~0.6μm,长度为3~5μm。添加二元烧结助剂会降低硼酸镁晶须的孔隙率并提高其抗压强度。当烧结助剂为Li2SO4-K2SO4时,孔隙率为48.37%,抗压强度为16.21 MPa;当烧结助剂为NaCl-KCl时,孔隙率为45.27%,抗压强度为16.39 MPa。

Mg2B2O5 whiskers were prepared by In-situ synthesis method using H3BO3 and CH4MgO6 as raw material. The obtained Mg2B2O5 whiskers were characterized by TG, XRD and SEM. The influence of sintering additives on the crystal structure and compressive strength of Mg2B2O5 whiskers were investigated. The experimental results show that the porosity of Mg2B2O5 whiskers is 62.57%, the compressive strength of Mg2B2O5 whisker is 10.32 MPa, the whisker diameter is 0.2 ~ 0.6 μm, and the length is 3 ~ 5 μm when no sintering aid is added. Addition of sintering aids reduces the porosity of magnesium borate whiskers and increases their compressive strength.